The word "怨天尤人" is formed by juxtaposing two verb-object phrases: "怨天" meaning "to blame heaven" and "尤人" meaning "to blame people". The characters "怨" and "尤" both convey the action of blaming or resenting, while "天" refers to fate or heaven and "人" refers to other people. This symmetrical combination directly creates the idiom's meaning of blaming external forces rather than oneself.